Message-ID: <d9be528c-af35-6c10-c458-9e2f7759bbb3@gmail.com>
Date:   Tue, 30 Nov 2021 10:56:26 -0700
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Subject: Re: [PATCH v2 net-next 00/26] net: introduce and use generic XDP
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To:     Jakub Kicinski <kuba@kernel.org>,
        =?UTF-8?B?VG9rZSBIw7hpbGFuZC1Kw7hyZ2Vu?= =?UTF-8?Q?sen?= 
        <toke@redhat.com>
Cc:     Alexander Lobakin <alexandr.lobakin@intel.com>,
        "David S. Miller" <davem@davemloft.net>,
        Jesse Brandeburg <jesse.brandeburg@intel.com>,
        Michal Swiatkowski <michal.swiatkowski@linux.intel.com>,
        Maciej Fijalkowski <maciej.fijalkowski@intel.com>,
        Jonathan Corbet <corbet@lwn.net>,
        Shay Agroskin <shayagr@amazon.com>,
        Arthur Kiyanovski <akiyano@amazon.com>,
        David Arinzon <darinzon@amazon.com>,
        Noam Dagan <ndagan@amazon.com>,
        Saeed Bishara <saeedb@amazon.com>,
        Ioana Ciornei <ioana.ciornei@nxp.com>,
        Claudiu Manoil <claudiu.manoil@nxp.com>,
        Tony Nguyen <anthony.l.nguyen@intel.com>,
        Thomas Petazzoni <thomas.petazzoni@bootlin.com>,
        Marcin Wojtas <mw@semihalf.com>,
        Russell King <linux@armlinux.org.uk>,
        Saeed Mahameed <saeedm@nvidia.com>,
        Leon Romanovsky <leon@kernel.org>,
        Alexei Starovoitov <ast@kernel.org>,
        Daniel Borkmann <daniel@iogearbox.net>,
        Jesper Dangaard Brouer <hawk@kernel.org>,
        John Fastabend <john.fastabend@gmail.com>,
        Edward Cree <ecree.xilinx@gmail.com>,
        Martin Habets <habetsm.xilinx@gmail.com>,
        "Michael S. Tsirkin" <mst@redhat.com>,
        Jason Wang <jasowang@redhat.com>,
        Andrii Nakryiko <andrii@kernel.org>,
        Martin KaFai Lau <kafai@fb.com>,
        Song Liu <songliubraving@fb.com>, Yonghong Song <yhs@fb.com>,
        KP Singh <kpsingh@kernel.org>,
        Lorenzo Bianconi <lorenzo@kernel.org>,
        Yajun Deng <yajun.deng@linux.dev>,
        Sergey Ryazanov <ryazanov.s.a@gmail.com>,
        David Ahern <dsahern@kernel.org>,
        Andrei Vagin <avagin@gmail.com>,
        Johannes Berg <johannes.berg@intel.com>,
        Vladimir Oltean <vladimir.oltean@nxp.com>,
        Cong Wang <cong.wang@bytedance.com>, netdev@vger.kernel.org,
        linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org,
        linux-rdma@vger.kernel.org, bpf@vger.kernel.org,
        virtualization@lists.linux-foundation.org
References: <20211123163955.154512-1-alexandr.lobakin@intel.com>
 <20211130155612.594688-1-alexandr.lobakin@intel.com> <871r2x8vor.fsf@toke.dk>
 <20211130090716.4a557036@kicinski-fedora-pc1c0hjn.dhcp.thefacebook.com>
From:   David Ahern <dsahern@gmail.com>
In-Reply-To: <20211130090716.4a557036@kicinski-fedora-pc1c0hjn.dhcp.thefacebook.com>
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On 11/30/21 10:07 AM, Jakub Kicinski wrote:
> On Tue, 30 Nov 2021 17:17:24 +0100 Toke Høiland-Jørgensen wrote:
>>> 1. Channels vs queues vs global.
>>>
>>> Jakub: no per-channel.
>>> David (Ahern): it's worth it to separate as Rx/Tx.
>>> Toke is fine with globals at the end I think?  
>>
>> Well, I don't like throwing data away, so in that sense I do like
>> per-queue stats, but it's not a very strong preference (i.e., I can live
>> with either)...
> 
> We don't even have a clear definition of a queue in Linux.
> 

The summary above says "Jakub: no per-channel", and then you have this
comment about a clear definition of a queue. What is your preference
here, Jakub? I think I have gotten lost in all of the coments.

My request was just to not lump Rx and Tx together under a 'channel'
definition as a new API. Proposals like zctap and 'queues as a first
class citizen' are examples of intentions / desires to move towards Rx
and Tx queues beyond what exists today.